dropzone.js (upload by drag and drop) does not work well.

. It has also been mounting as a reference for < p > or less.
http://plugmin.co/436/

Even if you try to drag and drop an image,
file://Users/...
I was unable to upload the file successfully.

as described in the file below console.log("hoge3") is passed, but
console.log("hoge4") does not pass.

I don't know how to do it, and I'm not very familiar with how to debug javascript, so I'm stuck.

I would appreciate your advice.

Thank you for your cooperation.

ruby 2.2.2
rails 4.0.3

Gemfile

source 'https://rails-assets.org'do
  gem 'rails-assets-dropzone'
end

app/assets/javascripts/application.js

//=require dropzone

$rake routes

index GET/index(.:format) public#index
  root GET/public#index
  upload POST / upload (.:format) public# upload

ImageUploader itself has been used elsewhere and has been able to upload images without any problems (although not drag and drop).

class Chat<ActiveRecord::Base
  mount_uploader: image, ImageUploader
end

class PublicController <ApplicationController
  def index
    @chat=Chat.new
  end

  default upload
    chat=Chat.find (params[:id])
    chat.attributes=chat_paramas
    chat.save
  end

  def chat_params
    param.require(:chat).permit(:user_id,:description,:image)
  end

end

app/views/public/index.html.erb

<div class="uploadArea">
  <%=link_to"", 'javascript:void(0), class:"uploadZone publish dz-clickable"%>
  <p>
    Drag and drop images!
  </p>
</div>

Also listed below in app/views/public/index.html.erb

*The script part disappeared when I put it in the tag format, so I will write it down as follows.
script type="text/javascript"

  $(function(){

      // If you want to post a value for something,
      var hogeParam="hoge";

      // charm
      Dropzone.autoDiscover=false;

      Dropzone.options.myAwesomeDropzone={
          paramName: "file", // input file name
          parallelUploads: How many files are uploaded at a time
          acceptedFiles: 'image/*', // If you only want to upload images
          maxFiles—Number of files that can be uploaded at a time of 10,//
          maxFilesize—0.5, // Maximum size of one file (1=1M)
          dictFileTooBig: "The file is too large. ({{filesize}}MiB).Maximum size: {{maxFilesize}}MiB.",
          dictInvalidFileType: "Not an image file.",
          dictMaxFilesExceeded: "You can upload up to 10 files at a time.",
      };
      // url puts the URL path to actually upload the image
      var myDropzone=new Dropzone(".uploadZone.publish", {url:'});

      console.log("hoge3")
      // If you want to post any value
      myDropzone.on("sending", function(file, xhr, formData){
          console.log("hoge4")
          formData.append("hoge",hogeParam);
      });
  });

/script

Additional information

Based on what Satoshi Sachin Ohmori pointed out, we have started
I was able to confirm the generation of the instance.

However, even if I drag and drop the image onto the browser, the image file will only be loaded, and I couldn't upload it.

There's no error log...

myDropzone:c
URL: URL()
_callbacks —Object
clickableElements:Array[1]
element —a.uploadZone.publish.dz-clickable
files —Array [0]
hiddenFileInput: input.dz-hidden-input
listeners:Array [2]
options:Object
previewsContainer: a.uploadZone.publish.dz-clickable
version: "4.2.0"
__proto__:c